WATERLOO, Iowa (AP) -- Outspoken congresswoman and tea party favorite Michele Bachmann cast herself as the "bold choice" for the Republican presidential nomination as she formally kicked off her campaign Monday in her Iowa home town.

Outside a historic mansion in Waterloo, Bachmann said she is waging her campaign "not for vanity," but because voters "must make a bold choice if we are to secure the promise of the future."

As a new Iowa poll this past weekend signaled she'll be a force in the state that opens the GOP nomination contest, Bachmann hopes to reshape the GOP field and how she's viewed by voters. After the formal Iowa kickoff, she planned to shift her focus to New Hampshire and South Carolina, other early voting states with traditions of separating the viable contenders from the political also-rans.

Bachmann, 55, has many wondering if the edgy side that turned her into a conservative star will be the one she shows on the presidential campaign trail. Her say-anything approach has earned her a loyal following but also plenty of guff from detractors who see her as a fringe politician. Past missteps have only redoubled her me-against-the-world view of politics.

"Her trick is going to be to maintain that boldness and to somehow rein it in and discipline it so it works for her and not against her," said GOP pollster Mike McKenna, who isn't working for any 2012 presidential candidates.

In March, she famously flubbed Revolutionary War geography. She told a group of students and conservative activists in Manchester, N.H. "You're the state where the shot was heard around the world in Lexington and Concord." Those first shots of the Revolutionary War were fired in Massachusetts, not New Hampshire. She later admitted she made a mistake.

For this campaign, she has surrounded herself with no-nonsense veterans of national politics, some of whom have deep ties to the political establishment Bachmann typically eschews. They include a trio of Eds: campaign manager Ed Rollins, pollster Ed Goeas and consultant Ed Brookover. In Iowa and New Hampshire, she's recruited aides who worked on the campaigns of previous presidential hopefuls Mike Huckabee and John McCain.

"I've been consistent, nothing but consistent," she said. "I don't say things for political value. I'm authentic in what I say."

Bachmann's unswerving style provides a sharp contrast with the more measured way of 2012 rivals, such as former Govs. Mitt Romney, Tim Pawlenty and Jon Huntsman and former House Speaker Newt Gingrich. Others vying for the nomination are ex-Sen. Rick Santorum, Texas Rep. Ron Paul and businessman Herman Cain.

A Des Moines Register poll published Sunday showed Bachmann and Romney far out front of the others in Iowa.

Bachmann's own climb has been swift, brushing off a school board race defeat just 12 years ago and moving rapidly from Minnesota's state Senate to Congress. In Washington, Bachmann vaulted to prominence by trying to block and now promising to repeal President Barack Obama's health care law. She has also tangled with GOP House leaders over her concerns they are too timid on federal spending cuts.

She's staunchly conservative on social issues, too, calling for more abortion restrictions and constitutional amendments to ban gay marriage.

In her latest national introduction, Bachmann has played up a softer side by highlighting her role in raising five children and 23 foster kids. But she's also gone hard at Obama, laying federal debt and deficits at his feet and accusing him of pushing the nation toward socialism.

David Strom, a Republican long involved in Minnesota politics, said it would be a mistake for Bachmann to sand down her edginess.

"She's not a maneuverer. At the end of the day she is going to distinguish herself by going out there and trying to draw people to her. I don't think she will try to become more nuanced as politicians tend to do," he said.

Those who have opposed Bachmann say she doesn't budge on her views, even in tough races.

Democrat Elwyn Tinklenberg, who lost to her in a 2008 congressional race, said he was frustrated that the more controversial Bachmann came off, the stronger she seemed to get. Her comments often fuel a fundraising machine that netted her $13.5 million for her last election.

"She can say something that's just outrageous and just completely wrong and move on and never skip a beat," Tinklenberg said.

Given the rise of the tea party movement, there may be even less reason for her to slide toward the political middle. Tea party members are seeking purity from the GOP candidates and have reacted skeptically to those largely linked to the party power brokers, particularly Romney.

"Truthfully, she's a hell of a lot closer to where the party is right now than where they are," McKenna said.